Unless otherwise indicated herein, the materials described herein are not prior art to the claims in the present application and are not admitted to be prior art by inclusion in this section.
Many access control systems exist to control access to, e.g., property. One type of access control system uses a lock and a corresponding key. Anybody in possession of the corresponding key can insert it into the lock to gain access to the property, such as a house accessed through a door with the lock or a swimming pool accessed through a gate with a lock. Another type of access control system uses an access card reader and access cards. Such access cards may be read by the access card reader by radio frequency (RF) communication or magnetically. Similar to lock and key access control systems, anybody in possession of an authorized access card can present it to the access card reader to gain access to a property. Both lock and key access control systems and access card access control systems control access to the property (or other resource) based on possession of a particular physical item, generally referred to hereinafter as token-based authentication.
Other types of access control systems control access to access-restricted resources based on possession of particular information, referred to as knowledge-based access control systems. For instance, combination/keypad locks control access by limiting access to anybody that knows a corresponding number combination, access code, password, or other information that can be entered through the combination/keypad lock. Such access control systems can also be implemented to control operational access to a computer by requiring a user to login with an authorized username and/or password, and/or to control access to online user accounts (e.g., email accounts, online banking accounts, online credit card cards, social media accounts), databases, services, information systems, or the like. In such access control systems, any user that knows the particular information can generally gain access to the computer, online user account, database, service, information system, or the like.
Still other types of access control systems control access based on what a person is, referred to as biometric access control systems. For instance, such access control systems may control access based on one or more measurable characteristics, e.g., biometric characteristics, of the person, such as fingerprints, DNA, or retinal patterns, to name a few. Biometric characteristics are distinctive, measurable characteristics of a person. In biometric-based access control systems, a person's biometric characteristics may be measured in advance and stored for later biometric authentication. When a person desires to gain access to the access-restricted resource, the person typically presents himself or herself to a biometric sensor of some sort (e.g., fingerprint scanner, retinal scanner) to newly measure the person's biometric characteristics. If the newly measured biometric characteristics match the stored biometric characteristics, the person's identity may be authenticated and the person may be granted access.
The subject matter claimed herein is not limited to embodiments that solve any disadvantages or that operate only in environments such as those described above. Rather, this background is only provided to illustrate one exemplary technology area where some embodiments described herein may be practiced.